周一到周五，每天一篇，北京时光早上7点准时更新~
If you think about it, most 3D graphics aren’t really 3D(用肾想象一下都知道，实际上3D图象其实不是真3D). We use 3D concepts and terminology to describe what something looks like; then this 3D data is “squished” onto a 2D computer screen(我们应用3D的概念和技巧来描写事物看起来如何，然后俺们就把这样的3D数据给"干"到了2D显示器上). We call the process of squishing 3D data down into 2D data projection(我们把3D数据变成2D数据的操作叫投影). We refer to the projection whenever we want to describe the type of transformation (orthographic or perspective) that occurs during vertex processing, but projection is only one of the types of transformations that occur in OpenGL(我们在这里讲到的投影是指发生在顶点处置阶段的OpenGL中的那些变换中的一个). Transformations also allow you to rotate objects around; move them about; and even stretch, shrink, and warp them(变换一样的许可你可以旋转物体、移动物体、揉、捏、掐等等都是可以的。反正就是让物体发生他们原来命运里就支配好的操作)If you think about it, m
